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Population a community of potentially interbreeding individuals at a given locality sharing a common gene pool.

Local population: “Population, subpopulation, deme”

Set of individuals that live in the same habitat patch and therefore interact with each other; most practically applied to “populations” living in such small patches that all individuals practically share a common environment and gene pool.

“any assemblage of discrete local populations with migration among them”

Populations that are spatially structured into assemblages of local breeding populations with migration between them that affects local population dynamics, including the possibility of reestablishment following extinction

“any assemblage of discrete local populations with migration among them”

Populations that are spatially structured into assemblages of local breeding populations with migration between them that affects local population dynamics, including the possibility of reestablishment following extinction

What is the difference to panmitic populations?

Contrast with panmictic population where every individual has equal likelihood of interacting with every other one !

one that meets ‘the minimum conditions for the long-term persistence and adaptation of a species or population in a given place’.

theoretically sufficiently large to protect against extinctions caused by harmful and unpredictable genetic, demographic or environmental factors over a given period of time (generally expressed in hundreds of years).

The environment including 'worst-case' eventualities that affect the viability of the population (continued):

The age structure of the individual population determines the fluctuations of population size.In addition, the totality of genetic resources of a species should have an age structure in order to have reproductive material continuously available for use, and for safety considerations.

Intrinsic rate of increaseand its spatial variation.

Sex ratio.In dioecious species the sex ratio is among the determinants of the completeness of pollination and the evenness of seed distribution. It varies also within species.

Dynamics of spatial distribution (size and distribution of patches).

Genetic variation (proportion and number of polymorphic gene loci and the numbers of their alleles).Pertinent information exists mainly about neutral marker loci.

The environment including 'worst-case' eventualities that affect the viability of the population (continued):

Heterozygosity.The previous and this term are often used as synonyms. It is true that without genetic variation there is no heterozygosity. However, heterozygosity is a parameter of the genotypic structure and does not directly measure genic variation.

Adaptability.Genetic variation is considered to be the sole basis of adaptability. Environmental degradation challenges adaptational processes in tree populations.

Spatial genetic structure.Restrictions on the transport distances of effective pollen and viable seed imply the development of spatial genetic structures. This is eventually enhanced or blurred by viability selection.

Assessing the likelihood that a population will persist over time, estimation of extinction probabilities by analyses that incorporate identifiable threats to population survival in to models of the extinction process.

Will a population fail or prosper in response to specific circumstances?

What is the risk of extinction for a population over a specific time, under a given set of circumstances?

Based on a model that relates a dependent variable (i.e. N) to the independent variables that influence it (weather, mortality, etc.), this relationship is mediated through parameters (i.e. survival rates, reproductive rates)

Simulations of individual populations can be run using this random variation to determine the probability of population extinction within a certain period of time or the mean time to extinction.

Can determine which parameter or combination of parameters most influences extinction probabilities

Management regimes that affect population parameters can then be developed and analyzed

Simulations of the impact of this management regime could be compared with the original population model to determine how it affects the probability that the population will persist in the future – can evaluate the effectiveness of management efforts